RESUMEN
Cyanide (CN-) is a highly toxic compound that exists in many substances and is harmful to the environment and human health. Therefore, it is of great significance to develop excellent CN- ion probes, especially solvent-induced on-off fluorescent probes. Based on the condensation reaction of indolo[2,1-b][1,3]oxazine molecules with aldehydes, probes (E)-13a-(2-(9-ethyl-9H-carbazol-3-yl)vinyl)-14,14-dimethyl-10-nitro-13a,14-dihydro-8H-benzo[e]benzo[5,6][1,3]oxazino[3,2-a]indole (NCO) and (E)-13a-(2-(9-benzyl-9H-carbazol-3-yl)vinyl)-14,14-dimethyl-10-nitro-13a,14-dihydro-8H-benzo[e]benzo[5,6][1,3]oxazino[3,2-a]indole (NBO) were synthesized to detect CN-. Compared with other cyanogen ion probes, NCO and NBO have special carbazole ring structures and large conjugate systems. When CN- is added to the probe-detection solution, color changes that are visible to the naked eye can occur. The UV-vis spectrum test using differential spectroscopy shows that the probe (i) has excellent solvent-induced switching characteristics and stability (CH3OH-H2O) and (ii) high selectivity, anti-interference ability, and sensitivity for the detection of CN-. The fluorescence limit of detections (LODs) are 1.05 µM for NCO and 1.34 µM for NBO. The UV LODs are 0.83 µM for NCO and 0.87 µM for NBO. Fluorescence spectroscopy shows that the probe has remarkable fluorescence properties. Fluorescence titration experiments, liver cancer cell (Hep G2) imaging, and cytotoxicity experiments all show that the probes have high biocompatibility, low toxicity, high cell permeability, and high sensitivity for the detection of CN- in cells. In addition, NCO and NBO have been successfully used for the detection of cyanogenic glycosides in the seeds of ginkgo, crabapple, apple, and cherry. Test strips were fabricated to detect CN-. After adding CN-, the color of the test strip changed significantly-from brown to light yellow; thus, the test strips have a high application value in the fields of drug quality control, drug safety testing, and pharmacological research.
Asunto(s)
Cianuros , Colorantes Fluorescentes , Carbazoles/toxicidad , Humanos , Extractos Vegetales , Espectrometría de FluorescenciaRESUMEN
The present study carried out a phytochemical investigation of the methanol extract of the branches and leaves of Clausena lansium and afforded nine carbazole alkaloids (compounds 1-9) including two new carbazole alkaloids, claulansiums A and B (compounds 1 and 2). The new compounds were elucidated on the basis of extensive spectroscopic data (MS, NMR, IR, and UV) and the known compounds were identified by comparing spectroscopic data with those reported in literature. All the isolated compounds were tested for their cytotoxic activity against A549 and Hela cancer cell lines. Our results showed that compounds 2-6 exhibited varying degrees of cytotoxicity to cancer cells, with IC50 values ranging from 8.67 to 98.89 µmol·L-1.
Asunto(s)
Alcaloides/química , Alcaloides/toxicidad , Clausena/química , Extractos Vegetales/química , Hojas de la Planta/química , Tallos de la Planta/química , Células A549 , Alcaloides/aislamiento & purificación , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/toxicidad , Carbazoles/química , Carbazoles/aislamiento & purificación , Carbazoles/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Estructura Molecular , Extractos Vegetales/toxicidad , Plantas Medicinales/químicaRESUMEN
Veterinary medicines can be extremely damaging to the environment, as seen with the catastrophic declines in Gyps vulture in South Asia due to their secondary exposure to diclofenac in their primary food source. Not surprisingly, concern has been raised over other similar drugs. In this study, we evaluate the toxicity of carprofen to the Gyps vulture clade through plasma pharmacokinetics evaluations in Bos taurus cattle (their food source) and Gyps africanus (a validated model species); tissue residues in cattle; and the effect of carprofen as a secondary toxicant as both tissue-bound residue or pure drug at levels expected in cattle tissues. Carprofen residues were highest in cattle kidney (7.72 ± 2.38 mg/kg) and injection site muscle (289.05 ± 98.96 mg/kg of dimension of 5 × 5 × 5 cm). Vultures exposed to carprofen as residues in the kidney tissue or pure drug equivalents showed no toxic signs. When exposed to average injection site concentrations (64 mg/kg) one of two birds died with evidence of severe renal and liver damage. Toxicokinetic analysis revealed a prolonged drug half-life of 37.75 h in the dead bird as opposed to 13.99 ± 5.61 h from healthy birds dosed intravenously at 5 mg/kg. While carprofen may generally be harmless to Gyps vultures, its high levels at the injection site in treated cattle can result in lethal exposure in foraging vultures, due to relative small area of tissue it is found therein. We thus suggest that carprofen not be used in domesticated ungulates in areas where carcasses are accessible or provided to vultures at supplementary feeding sites.
Asunto(s)
Carbazoles/toxicidad , Falconiformes , Drogas Veterinarias/toxicidad , Animales , Antiinflamatorios no Esteroideos/farmacocinética , Antiinflamatorios no Esteroideos/toxicidad , Asia , Carbazoles/farmacocinética , Bovinos , Muerte , Diclofenaco/farmacocinética , Diclofenaco/toxicidad , Semivida , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Toxicocinética , Drogas Veterinarias/farmacocinéticaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of M. koenigii Linn. Spreng (Rutaceae) have been used as traditional medicine for anxiety disorders. Aim of the study was to isolate antianxiety principle(s) from the leaves of M. koenigii using bioactivity guided approach. MATERIAL AND METHODS: Hydroalcoholic extract of M. koenigii leaves was prepared using soxhlet apparatus, and the same was evaluated for antianxiety activity at 250, 500 and 750mg/kg, po, using Elevated plus-maze (EPM). The extract was further partitioned successively with pet ether, chloroform, ethyl acetate and 1-butanol. All the fractions were evaluated for antianxiety activity. The bioactive ethyl acetate fraction was column chromatographed to get 5 fractions (F1-F5). All the fractions were evaluated for antianxiety activity using EPM. A pure compound, separated out from F2, was characterized using standard spectroscopic techniques, and its anxiolytic activity was evaluated using EPM. Antianxiety activity of isolated compound was further evaluated using Actophotometer and m-CPP induced anxiety model. TLC-densitometric method was developed to quantify mahanimbine in the plant. RESULTS: The present study resulted in the isolation of mahanimbine, which exhibits potent antianxiety activity at 3mg/kg, and the activity was statistically comparable to that of diazepam (2mg/kg). The developed TLC-densitometric method is specific, linear, precise, accurate, repeatable and robust. CONCLUSIONS: This study validates the ethnopharmacological use of M. koenigii leaves in the management of anxiety disorders. Mahanimbine is responsible for the antianxiety effect of M. koenigii leaves.
Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Carbazoles/farmacología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Murraya/química , Hojas de la Planta/química , Animales , Ansiolíticos/aislamiento & purificación , Ansiolíticos/toxicidad , Ansiedad/psicología , Carbazoles/aislamiento & purificación , Carbazoles/toxicidad , Modelos Animales de Enfermedad , Femenino , Compuestos Heterocíclicos de 4 o más Anillos/aislamiento & purificación , Compuestos Heterocíclicos de 4 o más Anillos/toxicidad , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos , Estructura Molecular , Actividad Motora/efectos de los fármacos , Pruebas de Toxicidad AgudaRESUMEN
BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) may cause gastrointestinal damage in dogs. HYPOTHESIS/OBJECTIVES: To determine the extent to which lansoprazole, liquorice extract, and a herbal solution exhibit protective effects on colonic mucosa when administered to dogs concurrently with the NSAIDs carprofen or robenacoxib. ANIMALS AND METHODS: Thirty-five healthy beagle dogs (15 male and 20 female) aged 13-14 weeks and weighing 4.3-5.5 kg at the beginning of the experiment were included. Endoscopy and biopsy of the caudal gastrointestinal tract were performed pretreatment and on the last day of a 21-day treatment period with (1) oral carprofen; (2) carprofen and the proton-pump inhibitor lansoprazole; (3) carprofen, liquorice extract, and a herbal solution that contained extracts of thyme, icelandic lichen, hyssop, and saponariae root; (4) robenacoxib; (5) robenacoxib and lansoprazole; (6) robenacoxib, liquorice extract, and herbal solution; or (7) an empty gelatin capsule. Statistical analyses were performed with the Kruskal-Wallis, Cochran's Q, and chi-squared test with p < 0.05 considered significant. RESULTS: Both carprofen and robenacoxib tested damaged the colonic mucosa with most severe microscopic lesions following administration of robenacoxib with lansoprazole. The risk of histopathological lesions in the colon increased most rapidly in robenacoxib with lansoprazole (absolute risk increase -0.85) similar to robenacoxib only (-0.75), whereas the best result was recorded following the plant remedies together with carprofen (-0.15) and the plant remedies together with robenacoxib (-0.2). CONCLUSIONS AND CLINICAL IMPORTANCE: Concurrent administration of liquorice extract and an herbal solution with robenacoxib was associated with decreased severity of the NSAID-induced mucosal lesions.
Asunto(s)
Antiinflamatorios no Esteroideos/toxicidad , Carbazoles/toxicidad , Difenilamina/análogos & derivados , Mucosa Intestinal/efectos de los fármacos , Lansoprazol/uso terapéutico , Fenilacetatos/toxicidad , Extractos Vegetales/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Animales , Colon/efectos de los fármacos , Inhibidores de la Ciclooxigenasa 2/toxicidad , Inhibidores de la Ciclooxigenasa/toxicidad , Difenilamina/toxicidad , Perros/metabolismo , Femenino , Glycyrrhiza , Masculino , PoloniaRESUMEN
The methanolic extract of Murraya koenigii leaf was screened for toxicological and biochemical effects on rats because of the folkloric uses as an anti-dysentery and anti-diabetes. The extract was moderately toxic (LD(50)=316.23 mg/kg body weight) to rats and had appreciable effect on the liver and kidney at higher doses leading to liver inflammation. It had little or no effect on haematology and relative organ weight of lungs, heart and spleen. Acute doses (500 mg/kg) reduced significantly serum globulin, albumin, urea, glucose, total protein, aspartate transaminase (AST), and increased cholesterol and alanine transaminase (ALT) indicating hepatic injury. However, chronic administration for 14 days gave a significant (p<0.05) reduction in the serum cholesterol, glucose, urea, bilirubin, ALT and AST showing that the plant has hypoglycaemic and hepatoprotective effects after prolonged use. The activity demonstrated by some of the isolated carbazole alkaloids and their derivatives against Trichomonas gallinae confirmed that the anti-trichomonal activity of the leaf may be due to its carbazole alkaloids. The order of activity was C(18)>C(23)>C(13). Girinimbine and girinimbilol with IC(50) values of 1.08 and 1.20 microg/ml were the most active. Acetylation of girinimbilol and mahanimbilol improved their activities to 0.60 and 1.08 microg/ml.
Asunto(s)
Alcaloides/toxicidad , Murraya/química , Murraya/toxicidad , Fitoterapia , Extractos Vegetales/farmacología , Trichomonas/efectos de los fármacos , Alcaloides/química , Estructuras Animales/efectos de los fármacos , Animales , Antitricomonas/farmacología , Antitricomonas/toxicidad , Carbazoles/farmacología , Carbazoles/toxicidad , Columbidae/parasitología , Recuento de Eritrocitos , Hematócrito , Dosificación Letal Mediana , Hígado/efectos de los fármacos , Nigeria , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Ratas , Suero/química , Suero/efectos de los fármacos , Suero/enzimología , Factores de Tiempo , Pruebas de Toxicidad Aguda/métodos , Trichomonas/aislamiento & purificaciónRESUMEN
Hepatocytes freshly isolated from male Wistar rats fed a common diet or a vitamin A- or vitamin E-supplemented diet (each for 21, 28, or 41 days) were assayed for sensitivity to DNA breakage and cytogenetic changes induced by carcinogens. Different indirectly acting carcinogens were assayed. N-nitrosomorpholine (NMOR) was the only agent that induced DNA breaks, chromosomal aberrations, and micronuclei in all experiments. Benzo[a]pyrene (B[a]p) and dimethyldibenzo [c,g]carbazole (diMeDBC) induced only DNA breaks in all experiments. Occasionally, B[a]P induced chromosomal aberrations and micronuclei, and diMeDBC induced micronuclei, but not chromosomal aberrations. These results demonstrated that the tested carcinogens assayed at concentrations highly effective in a hypoxanthine phosphoribosyltransferase/V79 system significantly increased DNA damage, while cytogenetic changes were less frequent. In hepatocytes from rats fed vitamin A, a reduction in the severity of all three end points was observed after NMOR treatment. After B[a]P treatment, we found a reduction in DNA breaks and chromosomal aberrations; after treatment with diMeDBC, we observed a reduction in DNA breaks. Treatment with vitamin E was less effective: it reduced DNA strand breaks induced by B[a]P and partially reduced those induced by diMeDBC and NMOR and the level of micronuclei induced by NMOR and B[a]P. Both vitamins reduced the level of DNA strand breaks induced by the oxidative effect of a visible light-excited photosensitizer.
Asunto(s)
Carcinógenos/toxicidad , Aberraciones Cromosómicas , Daño del ADN/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Vitamina A/administración & dosificación , Vitamina E/administración & dosificación , Animales , Benzo(a)pireno/toxicidad , Carbazoles/toxicidad , Células Cultivadas , Hepatocitos/ultraestructura , Masculino , Nitrosaminas/toxicidad , Ratas , Ratas WistarRESUMEN
Clarified slurry oil (CSO, CAS number 64741-62-4), a refinery stream produced by processing crude oil, is a developmental toxicant when administered dermally throughout gestation to pregnant rats. The manifestations of developmental toxicity observed included embryolethality and growth retardation; evidence of teratogenicity was limited, and not conclusive. The present study was undertaken to further explore the teratogenic potential of CSO. In an attempt to limit embryolethality and thereby promote detection of terata, CSO was administered once daily for a limited period of gestation [gestation days (GD) 9-12], via dermal application, to pregnant Sprague-Dawley rats at doses of 0, 10, 100, and 1000 mg/kg. All animals were sacrificed on GD 20. Detailed examination of the dams was performed. Due to the screening nature of this investigation, fetal evaluations were limited to body weight measurements, external examinations, and evaluation of select visceral endpoints. In the dams exposed to CSO, significant decreases in body weight [absolute and gain (GD 9-13, GD 0-20)] and in the amount of food consumed were observed at 100 and 1000 mg/kg. Additional evidence of maternal toxicity observed at 1000 mg/kg included decreased absolute and relative thymus weights, increased absolute and relative liver weights, and aberrant serum chemistry. Ingestion of the test material was evident at the high dose. Developmental toxicity was observed at 1000 mg/kg and included increased embryolethality, decreased body weight, and anomalous development (cleft palate, brachydactyly, edema). Although a low incidence of abnormal fetal development was observed at 100 mg/kg, it was not conclusive that the alterations were due to CSO exposure. It is likely that three to seven-ring polycyclic aromatic compounds present in CSO were responsible for the toxic effects observed.
Asunto(s)
Carbazoles/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Petróleo/toxicidad , Compuestos Policíclicos/toxicidad , Preñez/efectos de los fármacos , Administración Cutánea , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Carbazoles/administración & dosificación , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Femenino , Feto/anomalías , Feto/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Compuestos Policíclicos/administración & dosificación , Embarazo , Ratas , Ratas Sprague-Dawley , Reproducción/efectos de los fármacos , Bazo/efectos de los fármacos , Bazo/patología , Timo/efectos de los fármacos , Timo/patologíaRESUMEN
Clarified slurry oil (CSO), syntower bottoms (STB), and distillate aromatic extract (DAE) are refinery streams produced by processing crude oil. Each of these refinery streams is rich in both hydrocarbons having carbon numbers of C20 or greater and polycyclic aromatic compounds. Available data indicate that some refinery streams are developmentally toxic (manifested primarily as increased embryolethality and growth retardation) by the dermal route of exposure. However, there is no conclusive evidence for their being teratogenic. The present studies were designed to further explore the suspected teratogenic potency of refinery streams while at the same time limiting embryolethality. To profile teratogenic effects as a function of gestation day, pregnant rats received a single oral dose (2000 mg/kg) of CSO, STB, or DAE on one of gestation days (GD) 11-14; DAE and STB were also administered on GD 15. To profile effects as a dose response function, rats received a single oral dose of CSO, DAE, or STB on GD 12 at 125, 500, and 2000 mg/kg. Control animals were similarly treated but were administered tap water. On GD 20, dams were necropsied and the fetuses evaluated for normal development. In general, evidence of maternal toxicity (i.e., decreased body weight gain, decreased thymus weight) was observed at doses greater than or equal to 500 mg/kg. For each refinery stream tested, the incidence of resorption was greatest on GD 11. A common pattern of fetal malformations was observed for all of the refinery streams tested and included cleft palate, diaphragmatic hernia, and paw and tail defects. The incidence and type of malformation observed were influenced by the gestation day of exposure. The incidences of external and skeletal malformations were greatest on GD 11 and 12 for fetuses exposed to CSO; on GD 13 and 14, the incidence of malformation was comparable for CSO- and STB-exposed fetuses. The incidence of visceral anomalies was greatest on GD 11-13 for fetuses exposed to CSO and STB; on Gestation D 14, the incidence was comparable for each of the refinery streams tested. In general, the ability to produce adverse effects on development was greatest for CSO and least for DAE. Effects produced by STB were comparable to or less severe than those observed for CSO.
Asunto(s)
Anomalías Inducidas por Medicamentos , Huesos/anomalías , Carbazoles/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Petróleo/toxicidad , Compuestos Policíclicos/toxicidad , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Huesos/efectos de los fármacos , Carbazoles/administración & dosificación , Relación Dosis-Respuesta a Droga , Pérdida del Embrión , Femenino , Masculino , Tamaño de los Órganos/efectos de los fármacos , Compuestos Policíclicos/administración & dosificación , Embarazo , Ratas , Reproducción/efectos de los fármacosRESUMEN
Pregnant CD rats were exposed dermally to 0.05, 1, 10, 50, and 250 mg/kg/day of Clarified Slurry Oil (CSO) on Days 0-19 of gestation to determine its potential developmental toxicity. Untreated and vehicle controls were included in the study. Day 20 of gestation Caesarean-derived fetuses were examined for gross, external, and visceral or skeletal alterations. Dosages of 1 mg/kg/day and higher significantly decreased maternal body weight, body weight gain, feed consumption, gravid uterine weight, and live litter size and significantly increased resorption rate. These dosages also significantly reduced fetal weights and retarded development of the brain, kidney, thoracic and caudal vertebrae, metacarpals, and hindpaw phalanges in dosage groups with live fetuses (high dosage group dams resorbed all conceptuses). The 50- and 250-mg/kg/day dosage group dams had only placentas and/or dark red viscous fluid in the uterus or vagina and significant body weight loss (associated with resorption). The highest dosage also caused emaciation, slight dehydration, and swollen dark anogenital areas. These results indicate that CSO produces adverse developmental effects at maternally toxic dosages. The maternal and developmental NOAELs (no observed adverse effect levels) were 0.05 mg/kg/day. In a second study, groups of 10 mated female rats were exposed to "pulse" exposures and dosages of 1, 50, or 250 mg/kg/day of CSO applied dermally for 2- or 3-day intervals that spanned the gestation period. All dosages reduced maternal feed consumption and body weight gain during the treatment period. Dosages of 50 and 250 mg/kg/day also produced early resorptions when administered on Days 6 through 8 and 9 through 11 of gestation. However, no increase in fetal alterations occurred, indicating that the effects on embryo-fetal development were due to early death and not to the death of malformed conceptuses.
Asunto(s)
Carbazoles/toxicidad , Petróleo/toxicidad , Compuestos Policíclicos/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/patología , Administración Tópica , Animales , Carbazoles/administración & dosificación , Dermatitis por Contacto/patología , Ingestión de Alimentos/efectos de los fármacos , Femenino , Feto/efectos de los fármacos , Feto/patología , Tamaño de la Camada/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Compuestos Policíclicos/administración & dosificación , Embarazo , Ratas , Ratas Endogámicas , Piel/patología , Útero/anatomía & histología , Útero/efectos de los fármacos , Útero/crecimiento & desarrollo , Aumento de Peso/efectos de los fármacosRESUMEN
Refinery streams are complex mixtures, but of a relatively few homologous series of hydrocarbons (paraffins, olefins, naphthenics, and aromatics). Studies were performed to determine if systemic and developmental toxicity were related to the presence and levels of certain classes of refinery stream components. We have performed systemic toxicology studies in the rat on 13 refinery streams: Clarified Slurry Oil, Coker Light Gas Oil, Distillate Aromatic Extract, Heavy Atmospheric Gas Oil, Heavy Coker Gas Oil (from three refineries), Heavy Vacuum Gas Oil, Light Catalytically Cracked Naphtha, Light Cycle Oil, Syntower Bottoms, Vacuum Tower Overhead, and Visbreaker Gas Oil. Rats were exposed via repeated dermal administration (daily) at several dose levels. Developmental toxicology studies were performed on these same streams with the following exceptions: only two Heavy Coker Gas Oils were tested and Visbreaker Gas Oil was not tested. End points for systemic toxicity (13-week) studies included skin irritation, body and organ weights, hematology, and serum chemistry; for developmental toxicity studies some of these same end points (excluding hematology) were considered, but they also included resorption and fetal body weight. In general, toxicity was correlated with concentrations of polycyclic aromatic compounds (PAC) composed of 3, 4, 5, 6, and/or 7 rings (decreased thymus weight, increased liver weight, aberrant hematology and serum chemistry, increased incidence of resorption, decreased fetal body weight), PAC containing nonbasic nitrogen heteroatoms (increased mortality, decreased body weight, decreased thymus weight, increased liver weight, decreased hemoglobin content and hematocrit level, decreased fetal body weight), and/or PAC containing sulfur heteroatoms (decreased red blood cell and platelet counts, increased sorbitol dehydrogenase.)(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Carbazoles/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Petróleo/clasificación , Petróleo/toxicidad , Compuestos Policíclicos/toxicidad , Animales , Carbazoles/análisis , Femenino , Hígado/efectos de los fármacos , Masculino , Pruebas de Mutagenicidad , Tamaño de los Órganos/efectos de los fármacos , Petróleo/análisis , Compuestos Policíclicos/análisis , Ratas , Ratas Sprague-DawleyRESUMEN
The antitumor properties of 7H-pyridocarbazole dimers, a new series of bifunctional intercalators, have recently been described (Pelaprat, D. Delbarre, A., Le Guen, I., Roques, B. P., and Le Pecq, J. B. J. Med. Chem., 23: 1336-1343, 1980; and Roques, B. P., Pelaprat, D., Le Guen, I., Porcher, G., Gosse, C., and Le Pecq, J. B. Biochem. Pharmacol., 28: 1811-1815, 1979). In order to study the mechanism of action of these compounds, an L1210 subline was made resistant to one dimer (NSC 335153; ditercalinium). Selection of resistant cells was based on an in vitro-in vivo procedure as follows. Ascitic cells were taken from a leukemic mouse and incubated in vitro with the dimer for 1 hr. They were then injected into mice. After the development of the ascites, L1210 cells were collected and the process was repeated 13 times, until establishment of the resistance. Cloned resistant cells have maintained their resistance for 18 months of in vitro culture. The effects of two dimers (NSC 335153 and NSC 335154) on cell viability, growth, colony formation, and cell cycle progression were investigated on parental and resistant L1210 cells. The cross-resistance of these two L1210 cell lines to several cytotoxic agents was estimated. Several observations indicate that the mechanism of action of these dimers might be different from that of monointercalating agents: (a) these drugs induce a delayed toxicity (growth arrest occurring five generations after drug exposure) in sensitive but not in resistant cells; (b) cells exposed to the dimers arrested almost randomly in all phases of the cell cycle, whereas the corresponding monomer provokes a block in the G2 + M phase. Resistant cells were cross-resistant to 7H-pyridocarbazole monomer, Adriamycin, and vincristine but not to 6H-pyridocarbazole monomer derivatives, actinomycin D, and methotrexate.
Asunto(s)
Carbazoles/toxicidad , Leucemia L1210/patología , Animales , Antineoplásicos/toxicidad , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Resistencia a Medicamentos , Cinética , Leucemia L1210/tratamiento farmacológico , Ratones , Relación Estructura-ActividadRESUMEN
New modifications of 10-[[3-(diethylamino)propyl]amino]-6-methyl-5H-pyrido[3',4':4,5]pyrrolo[2,3-g]i sisoquinoline (1b) and 1-[[3-(diethylamino)propyl]amino]-9-methoxy-5,11-dimethyl-6H-pyrido[4,3-b]carba zole (4b), which display important antitumor properties, were performed either on the side chain or on the intercalating heterocycle. Side chains were introduced by direct substitution of the corresponding chloro derivatives and 6-N-methyl-9-hydroxypyrido[4,3-b]carbazoles analogues were prepared via 9-O-benzoyl-1-chloroellipticines. Evaluation of all new compounds shows no significant increase of in vitro cytotoxicity and percent ILS on the L1210 leukemia system by comparison with the model compounds 1b and 4b.